If you have ever owned an Android device, you must have come across the word “Custom ROMs”. They bring various usability features and tweaks, the latest version of Android, performance improvements and more.  So, what are custom ROMs? How are they useful?

What are custom ROMs?

In a nut shell, custom ROMs are aftermarket firmwares modified by a bunch of talented developers in their pastime. Even with limited resources and time, these developers are able to achieve what many giant OEMs fail to do — bring the latest version of Android to a handset within weeks of it being released, or fix a bug in just a mere few days.

The barrier to installing a custom ROM in any Android device is pretty high and with root access being an absolute necessity [For more information about rooting, be sure to check these Rooting 101 guides: what it is, what to do before you root, and how to find the best ways to root]. But even with root access, installing a custom ROM requires the user to go through several guides and make sure that they have downloaded the right files meant for their specific device.

However, the end result is almost always worth it as they bring access to a wider range of features, dramatically improve performance and more.

Different types and their usefulness

Custom ROMs are generally of two types: Stock firmware based and AOSP based.

Stock firmware based custom ROMs: These ROMs are a modified version of the stock firmware that your device shipped with. Sometimes, they can also be based on an upcoming leaked firmware that some developer managed to get his hands on. These types of custom ROMs offer the most stability but only have a limited feature set.

However, they do offer a great way to fix those minor niggles that you might have with the stock firmware and add just the right amount of enhancements.

AOSP based custom ROMs: These ROMs are based on the Android Open Source Project (AOSP) and are almost always built on the latest version of Android. Since they are based on AOSP, they are devoid of any kind of OEM skin and look just like vanilla Android.

AOSP based ROMs are a great way of bringing the latest version of Android to devices that are more than capable enough of handling it but were ditched by its OEM. They pack in many unique features like multi-window, Halo, PIE, DSP Manager and more. Here is a quick feature walkthrough of CyanogenMod 11 M2, one of the most popular custom ROMs out there. This should give you a good idea about what to expect in the features department from AOSP based ROMs.

The downside is that since they are somewhat hacked by individuals to make AOSP work on hardware it was not meant for, these kind of ROMs can be a bit unstable or have one or the other hardware functionality broken, which might be a deal-breaker to many.

Tomorrow, we will tell you about the difference between custom ROMs and rooting, and how custom ROMs differ from installing any kind of mod on your device, so stay tuned!